Fernando Alonso was in a positive mood after free practice in Friday, despite ending the day a modest seventh.

However, headline times don’t always tell the full story, and the Spaniard insisted that Ferrari made progress.

“This was a good day, even if in the morning we, and in fact everyone, lost time because of the rain, and so in the afternoon we found ourselves facing double the workload,” he said. “Before drawing any conclusions, we need to wait for the analysis of the data acquired this afternoon from both cars. Felipe (Massa, teammate) and I tried different aero configurations, with more and less downforce, which will be the real key to this race, along with the weather.

“In terms of today’s times, we have got closer to the favorites, but I’m not sure which weather forecast I would prefer. It’s true that in the rain, the cards on the table can be shuffled up, but in the wet there are as many chances to benefit as there are to lose.”

Pirelli’s Paul Hembery believes that something on the track was the likely cause in most cases, while also suggesting that a piece of debris was responsible for the Vettel problem.

Inevitably, given the events of Silverstone and the high-speed nature of Spa, teams and drivers are looking for some reassurances from Pirelli.

“It looks on the Red Bull as if something has been rubbing on the surface and then cut straight through the surface,” said Hembery. “And on the Ferrari there are two quite clear holes through the top of the tread. We’ve got to go and look at the track later and see what’s been turns 13 and 15.

Lewis Hamilton had a difficult first day at Spa, finishing FP2 only 12th and some 1.420 seconds off pace-setter Sebastian Vettel after struggling to find one-lap speed.

Hamilton, who came to Belgium on the back of his Hungarian GP win, said he lacked grip with the low downforce specification used at Spa.

“We have some work ahead of us this evening to get the car feeling just right, but overall today was a reasonable start to the weekend,” he said. “The car feels very different here with the low downforce setup, compared to at the last race, and we need to refine a few areas to get the balance sorted.

“We were able to get some good long-run work done today, and that’s the most important thing for the race. We’ve got time to make the changes required, so I’m optimistic that tomorrow will see an improvement.”

Sebastian Vettel posted the fastest time before his rear tire punctured in Friday’s second practice at the Belgian Grand Prix.

The three-time defending Formula One champion had to stop with about 20 minutes of the session remaining when his right rear tire popped and the loose rubber flapped around as he made his way back to the pits.

The German had earlier clocked 1 minute, 49.331 seconds, which was .059 quicker than Red Bull teammate Mark Webber and .818 faster than Lotus driver Romain Grosjean. While it was not immediately clear what caused the puncture, it could be unwelcome news for Pirelli given the furor surrounding its fast-shredding tires throughout the season. With his session over, Vettel stood alongside officials in the garage as they studied the car’s data.